Breath has long been known to have valuable biomarkers for spotting early stage lung cancer. Handling breath samples has been logistically difficult, with most tests requiring processing to be done rapidly onsite. While studies have shown that dogs can be trained to smell lung cancer, the concentrations of biomarkers is so low that research has been plagued with inconsistent results, given the existing protocols. Small deviations in the way that samples are handled often leads to erroneous results.
Volatile organic compounds (VOCs) make up the majority of the scents and smells human and animals can sense. While smell has not been formally used in routine medical practice, there are well known scents associated with particular conditions. For example, the smell of death is created by VOCs, in particular putrescine and cadaverine, which are released when cells die. Other VOCs, such as ketones, are exhaled if there is not enough insulin to help the body use sugar for energy. Lung cancer has over 40 known VOCs that researches have shown can indicate lung cancer.
A major challenge in measuring the VOCs in breath is the complexity of the sample. There are over 1,000 known compounds in breath. Trying to separate and measure all these compounds has been a logistical challenge for makers of devices. Simple devices often can only measure a class of compounds, or have unknown specificity and selectivity towards different VOCs.
Devices used in research have suffered from being very complex to use, making them difficult to deploy in a standard clinical environment, or they have been to very expensive to use making them unattractive for a screening test. It is therefore appreciated that there is a need in the art for a small and inexpensive device that can be used to capture biomarkers in the breath.